Fig. 1

The circRNA expression profile in the spinal cord of morphine-tolerated and sham rats. a. Heat map generated by hierarchical clustering of differentially expressed circRNAs in 4 MT and 4 NS samples; the highly- and lowly-expressed circRNAs are represented in red and green respectively; b. The box plot shows the enrichment of total circRNAs in each sample; c. The red spots in the volcano plot represented the differentially expressed circRNAs with statistical significance; d. Scatter plot illustrated the normalized circRNA expression in both groups. The x-axis represented the circRNA level in NS group, the y-axis represented the circRNA level in MT group, circRNAs distributed above the top green line or below the green bottom line are the ones with a between-group fold change more than 2.0; e. The classification of DEcircRNAs based on their origin, most DEcircRNAs were originated from exons. f. The chromosome distribution of DEcircRNAs: the host genes of DEcircRNAs were distributed in all chromosomes. MT, morphine tolerance; NS, normal saline